Grinder and shredder



H; J. SHELTON.

GRINDER AND SHREDDER. I! APPLICATION man DEC.6,1919.'

Patented 001;.

W m m 7 m I PATENT OFFICE.

HARRY J". SHEL'ION, OF ST. LOUIS, MISSOURI.

GRINDER AND SHREDDER.

T 0 all whom it may concern:

Be it known that I, HARRY J. SHELTON, a citizen of the United States, residing in the city of St. Louis and the State of Missouri, have invented a new and useful Improvement in Grinders and Shredders, of which the following is a full clear, and exact specification, reference being had to the accompanying drawings, which form a part thereof.

My invention relates to grinders and shredders which have a plurality of hammers rotatably mounted in a casing and in which substantially the entire lower half of the casing has its circumferential wall formed of a screening plate through which the material is passed after it has been acted upon by the hammers. In such machines the screening plate has its side edges lying in grooves formed in the end walls of the machine, there being a continuous groove in each end wall. The screening plate is held in place by means of clamping and packing devices placed in the grooves in such a way as to clamp the side edges of the screening plates in place. The frame of such machines is usually made in two halves which are separable along a horizontal median plane. The screening plate has its ends lying substantially on a level with the upper surface of the lower half of the frame, and it often happens when in use that part of the ends of the screening plate which lie between the grooves formed in the end wallsv of the frame will become slightly bent inwardly toward the center of the machine and thus become slightly separated from the adjacent sidewalls of the frame, with the result that there will be at this point an open space through which unground material may pass outside of the grinding chamber without passing through the screening plate.

The object of my invention is to provide cover plates whereby the ends of the screening plate will be prevented from springing inwardly; and a further object of my invention is to provide a cover plate whereby material will be prevented from passing between the side walls of the frame of the ma chines and the ends of the screening plate; and a still furtherobject of my invention is to provide a cover plate that may be used with screening plates of different thicknesses to prevent the passageof unground material between the ends of. the screening plate and the walls of the machine.

Specification of Letters Patent.

. Patented Oct. 26, 1920.

Application filed December 6, 1919. Serial No. 342,952.

Fig. 2; and Fig. 4 is an enlarged sectional view along the line 4-4 of Fig. 1.

Referring to the figures, 1 represents the walls of the lower half of the frame of a grinding ahd shredding machine in which are mounted the hammers 2 which are attached to the disk 3 fastened upon the shaft 4. 'The shaft 4 is rotatably mounted in suitable bearings, not shown, carried by the end walls of the frame, so that the hammers may be made to revolve in the machine to properly grind and shred material fed thereto. In each end wall there is formed a groove 5 of substantially a semicircular shape. 7 is a screening plate whose side edges project into the groove 5 and which is held in place by means of the packing and clamping members 6. In the preferred form, the outer circumferential wall of the groove 5 is made axial and the inner circumv ferential wall is inclined at an angle as shown in Figs. 2, 3 and 4. The clamping and packing member 6 for each groove is, preferably, made of a single piece of material having its outer face axial and its inner face inclined at the same angle as the inner wall of the groove 5. The packing and clamping ring 6 is also, preferably, made of resilient material so that when it is forced into the groove 5 the action of the inclined face of the ring 6 on the inclined wall of the groove 5 will cause the ring to expand or move outwardly radially and thus clamp the screening plate 7 between the outer face of the ring 6 and the outer wall of the groove 5. In order to force the ring 6 into the groove 5 there are provided for packing rings '6 in the machine so that their side edges are clamped in place and material is prevented from leaving the grinding chamber through the grooves 5. 11 is a cover plate which is, preferably, of an annular cross-section and formed with a horizontal member and a vertical member and which covers and extends across the end of the screening plate ,7 between the grooves 5 formed in the endwalls of the frame of the machine. In order that the upper surface of the horizontal member of thecover plate 11 shall not extend above the top surface of the lower half of the frame of the machine, there is formed in said surface a recess 12 in which the horizontal member of the cover plate may lie. The depth of this recess 12 is such that the upper surface of the cover plate 11 will be as nearly as possible on a level with the upper surface of the lower half of the frame 1. The vertical member of the cover plate 11 hangs down inside of the screening plate 7 as shown in Figs. 1 and 3, and in order that the cover'plate 11 may be engaged by the packing and clamping ring 6 there is formed in each of these rings at each end thereof a notch 13 into which the end of the cover plate projects as shown in Figs. 2 and 3. The notch 13 is made of a depth substantially equal to the thickness of the metal forming the vertical member of the cover plate 11, so that when the clamping ring 6 is in place it presses not only upon the screening plate 7, but also upon the vertical member of the cover plate 11 so as to prevent the cover plate from moving inwardly and thus tends to retain the cover plate in place. The cover plate 11 is made of such a length that when a screening plate 7 of the thinnest material is used and the packing and clamping rings 6 are drawn to their fullest extent into the grooves 5, the notches 13 will still engage the ends of the cover plate 11. When the upper half of the frame of the machine is in place its walls will rest on the cover plates distance of the center of the shaft 4- above the lowest point of the groove 5, as shown in Fig. 1. This deviation of the ends of the groove 5 from the true semicircle is such that the inner faces of the covers 11 are substantially the same distance from the ends of the hammers 2 as is the inner surface of the" grinding plate 7 at its lowest point, as shown in Fig. 1. The cover plate 11 covers and retains in place the ends of the screening plate 7 and prevents inward movement thereof and at the same time prevents the passage of material from the grinding chamher past the ends of the screening plate.

In. order to assist in holding the end walls of the machine together tie-rods 15 are proengaged bysaid packing and clamping means whereby said cover plates are prevented from moving inwardly of said machine.

2. A grinding and shredding machine comprising end walls each of which has a substantially semicircular groove formed therein, a screening plate having its side edges lying in said groove, packing and clamping means whereby said screening plate is retained in said grooves, and separably removable cover plates each having a horizontal and a vertical member adaptedto cover and retain in place the ends of said screening plate between said grooves, the horizontal members of said cover plates lying in Y recesses formed in the upper surface of the lower half of the frame of said machine.

3. A grinding and shredding machine comprising end walls each of whichhas a substantially semicircular groove formed therein, a screening plate having its side edges lying in said grooves, packing and clamping rlngs whereby said screening plate is retained in said grooves, and separably removable cover plates each having a hori zontal and a vertical member adaptedto cover and retain in place the ends of said screening plate between said grooves, the horizontal members ofsaid screening plates lying in recesses formed in the upper surface of the lower half of the frame of said machine and the ends of said cover plates being engaged by said packing and clamping rings whereby said cover plates are prevented from moving inwardly of said machine.

4. A grinding and shredding machine comprising end walls each of which has a substantially semicircular groove formed therein, a screening, plate having its side edges lying in said groove, radially expanding packing and clamping rings whereby said screening plate is retained in said grooves, and separably removable cover plates each having a horizontal and a vertical member adapted to cover and retain in place the ends of said screening plate between said grooves, the horizontal members of said cover plates lying in recesses formed in the upper surface of the lower half of the frame of said machine.

5. A grinding and shredding machine comprising end walls each of which has a substantially semicircular groove formed threin, a screening plate having its side edges lying in said grooves, radially expanding packing and clamping rings whereby said screening plate is retained in said grooves, and separably removable cover plates each having a horizontal and vertical member adapted to cover and retain in place the ends of said screening plate between said grooves, the horizontal members of said screening plates lying in the 'ilppersurface of the lower half of the frame of said machine and the ends of said cover plates being engaged by said packing and clamping rings whereby said cover plates are prevented from moving inwardly of saidmachine.

In witness whereof I have signed my name to this specification.

HARRY J. SHELTON. 

